277. Device used as a standard for the calibration of pressure gauges is a
A. Bellow
B. Diaphragm
C. Dead weight pressure tester
D. Mercury manometer
✅ The correct answer is option C.
279. The activity of pure hydrogen gas at 1000°C and 5 atm pressure
A. Is always less than 1
B. Is always greater than 1
C. Can be 5
D. Depends on the choice of the standard state
✅ The correct answer is option D.
281. In an isochoric process,
A. There is no transfer of mass and energy
B. Free expansion of an ideal gas occurs
C. No mechanical work is done by the system
D. All of the above
✅ The correct answer is option C.
283. Which of the following alloying elements reduces the formation of iron sulphide in steel?
A. Cobalt
B. Nickel
C. Manganese
D. Vanadium
✅ The correct answer is option B.
285. Permanent set in a material is produced by subjecting it to
A. Triaxial loading
B. Fatigue loading
C. Stresses beyond the elastic limit
D. Tensile & compressive loads simultaneously
✅ The correct answer is option C.
287. Circular cross section machine parts which are symmetrical about the axis of rotation are made by hot
A. Piercing
B. Spinning
C. Drawing
D. Extrusion
✅ The correct answer is option B.
290. Out of the following surfaces, the emis-sivity will be minimum for
A. Aluminium foil
B. Concrete
C. Plaster
D. Smooth glass
✅ The correct answer is option B.
293. Spherical shape of mercury droplets is due to its
A. High viscosity
B. Low surface tension
C. High density
D. High surface tension
✅ The correct answer is option D.
296. The yield point in fatigue loading compared to that in static loading is less. The ratio of ultimate tensile strength to endurance limit of a material subjected to fatigue loading is
A. 0.5
B. 1
C. 1.5
D. 2
✅ The correct answer is option D.
299. An abrupt and sudden fall in the readinp of barometer is an indication of the
A. Storm
B. Rain
C. Clear weather
D. Cold wave
✅ The correct answer is option A.